The present invention relates to a fan duct for a turbomachine such as an aircraft turbo-jet engine.
The fan duct (often referred to as a “bypass duct”) of a turbomachine extends around the engine of the turbomachine, between the fan and the exhaust pipe, and comprises two substantially cylindrical coaxial walls which define therebetween an annular flow space for one portion of the air drawn in by the fan, forming a cold flow or secondary flow. The other portion of the air drawn in by the fan passes into the engine of the turbomachine which comprises, from upstream to downstream, a compressor, a combustion chamber and a turbine, and forms the hot flow or primary flow.
The internal wall of the duct is fixed at its upstream end to an intermediate housing of the turbomachine and is connected at its downstream end to an exhaust housing. It is shaped to surround the engine of the turbomachine at a short radial distance.
The external wall of the duct is fixed at its upstream end to the intermediate housing and at its downstream end to a suspension and centering system which is connected to the exhaust housing and which is generally located upstream of a thrust reversing system. It ensures the aerodynamic shaping of the secondary flow and may also play a structural role in the transmission of forces such as the suspension forces of the engine or thrust reversing forces and minimizing the occurrence of distortion of the carcass in the turbo-jet engine.